The objectives of this investigation are 1) to develop a removable dental model (RDM) for investigations of developing fissural dental plaque and 2) to clearly identify patterns of bacterial succession and changes in formation of major by-products of carbohydrate metabolism in fissural dental plaque during normal dietary intake, during periods of high and low salivary exposure, during periods of exposure to high levels of sucrose or glucose, and during experimental induction of dental caries. Dental student volunteers will fabricate and wear acrylic, Hawley-type, palatal appliances containing 2 to 4 occlusal segments of extracted teeth (the RDM) for periods of from 1 to 21 days. Salivary exposure of the fissures will be controlled by mechanical barriers in the fissures and substrate levels by application of minute quantities of sucrose or glucose to the dental inserts. The dental inserts will be removed periodically and incubated in an anaerobic chamber with 14C-labelled sucrose or glucose for 15 minutes. The major metabolic by-products will then be quantitated. The bacteria will be dislodged from the inserts, cultured and identified. Caries formation in the central inserts will be determined by histological techniques.